With the development of personal communication, everybody possesses more and more communication devices, such as the mobile phone, the PHS (Personal Handyphone System) phone, the fixed telephone and the like, each of which has a different telephone number. For the convenience of users, the telecom operators provide ‘ONLY’ (One Number Links You) service. ‘ONLY’ is a kind of intelligent telephone number. An ONLY user may set different call transfer numbers according to his requirements. When someone else dials an ONLY number, the system will call the ONLY user automatically in accordance with the preset communication mode, the set order of the telephones and the way for calling so as to establish a call.
The communication mode of an ONLY user can be set as simultaneous ringing, sequential ringing or advanced ringing.
An ONLY user may register the numbers of multiple terminals in advance if he chooses the function of simultaneous ringing. When there is an incoming call, the multiple registered terminals will ring simultaneously, and after the user chooses to answer on one of the terminals, the other terminals will stop ringing. The ONLY service may support simultaneous ringing of multiple terminals, and a user may set the function according to his need.
To avoid the inconvenience of other people memorizing multiple telephone numbers, a user can publish one ONLY number, while his mobile phone, PHS and fixed telephone all being set as the ONLY-bonded (transfer) number. All the calls to the ONLY number will be automatically transferred to the bonded number (mobile phone, PHS or fixed telephone) by the system according to the user's setting. Furthermore, the bonded numbers can ring simultaneously, and the user can choose any one of the terminals to answer the call for his convenience.
Since the multiple simultaneous ringing numbers bonded with the ONLY number may be numbers in a network such as local home network, local other network, long distance telephones and the like, which possibly relates to disbursement and settlement between different networks, the charges between the ONLY number and the simultaneous ringing numbers need to be calculated during the operation of the ONLY service, and they will be calculated according to the duration of the call.
If the simultaneous ringing numbers bonded with an ONLY number is more than two, in practical applications, it is necessary to know which terminal is off-hook and answering during a call, and the corresponding charges between the ONLY number and the terminal which is off-hook and answering will be calculated according to the corresponding billing rate and the duration of the call.
However, there is no effective method provided in the prior arts to calculate the call charges between an ONLY number and simultaneous ringing numbers.